Can someone share some differences in these 2 rear ends? thanks
8 3/4 has a carrier that loads from the front of the housing. You can pull the center section out and rebuild it outside of the car. The Dana 60 has a rear cover plate and the ring gear/pinion loads from the rear. The 8 3/4 is a lot easier to change axle ratios, just drop in a different center section.
All RB 4 speed E bodies came equipped with a Dana 60 as mandatory. RB autos had 8 3/4's as standard equipment. You could pay the $$ and get a Dana 60 as an optional rear.
Dana 60's are pretty bullit proof, but on a street car that does not see a lot of track use with slicks, an 8 3/4 will hold up fine. The tires act as a fuse, too much torque applied and the tires will blow off before the rear grenades. Now apply some traction and torque levels above 500 lbs/ft or so...better invest in the Dana.